FDA expands Bravecto Quantum label for two more dog tick species

Merck Animal Health has won an FDA label expansion for Bravecto Quantum, adding 12-month treatment and control claims in dogs for two more species: the Asian longhorned tick and the Gulf Coast tick. The March 18, 2026, approval builds on Bravecto Quantum’s original July 10, 2025, FDA approval as the first long-acting flea and tick treatment for dogs, delivered as a single subcutaneous injection by a licensed veterinarian. (merck-animal-health-usa.com)

That original approval was already notable because it gave practices a clinic-administered option with longer duration than standard monthly flea and tick products. FDA said at the time that Bravecto Quantum protects dogs against fleas and ticks for 8 to 12 months, depending on the tick species involved, and restricted prescribing to licensed veterinarians because administration, adverse-event monitoring, breeding-use counseling, and interval selection require professional judgment. (fda.gov)

The new label specifically adds Haemaphysalis longicornis and Amblyomma maculatum for 12 months after a single veterinarian-delivered injection. Merck says the product continues to be indicated to kill adult fleas, treat and prevent flea infestations, and control black-legged, American dog, and brown dog ticks for 12 months. The exception remains lone star ticks: exposure risk to Amblyomma americanum still means an 8-month interval, not a once-yearly schedule for every dog. (merck-animal-health-usa.com)

That distinction matters because it has already become a live marketing issue. Earlier this month, BBB National Programs’ National Advertising Division said Merck had support for describing Bravecto Quantum as a safe, effective year-round option, but recommended the company discontinue or revise claims that suggested one injection provides a full year of tick protection for dogs generally. NAD said those claims need to clearly communicate the 8-month re-dosing interval for dogs with potential lone star tick exposure, and Merck said it would appeal parts of that decision. (bbbprograms.org)

From a parasite-control standpoint, the expansion also lands as the Asian longhorned tick continues to draw veterinary and livestock attention in the U.S. USDA APHIS describes it as an invasive tick and maintains county-level tracking of established populations. CAPC, meanwhile, continues to recommend year-round tick control for dogs because ticks can transmit a wide range of pathogens to pets and people and may be active throughout the year. The Gulf Coast tick is also clinically relevant in companion animal medicine, including as a vector associated with canine hepatozoonosis. (aphis.usda.gov)

Why it matters: For veterinary professionals, this is less about a brand-new product than about a more complete label for a product that could fit annual preventive workflows. A veterinarian-administered injectable can improve adherence by reducing dependence on monthly pet parent compliance, but it also shifts more responsibility to the clinic to assess geography, seasonality, species exposure, and the dog’s neurologic history. FDA’s class warning on isoxazolines still applies; the agency says products in this class have been associated with neurologic adverse reactions, including muscle tremors, ataxia, and seizures in some dogs and cats, even though they are considered safe for most animals. (fda.gov)

There’s also a competitive angle. Other fluralaner products already have Asian longhorned tick claims in shorter-duration formats, including Bravecto chews, so the real significance here is pairing broader species coverage with the longest labeled duration in a single veterinary-administered dose. For practices, that may strengthen the case for using Bravecto Quantum in dogs whose preventive plans are tied to annual visits, while preserving a need for careful counseling in lone star tick regions. (merck-animal-health-usa.com)

What to watch: Next steps are likely to include updated promotional language, possible fallout from Merck’s appeal of the NAD decision, and closer attention from practices to how the company positions “year-round” protection in areas where lone star tick exposure keeps the dosing interval at 8 months. (bbbprograms.org)